Ventricular Septal Defects

There are two sides to the heart, separated by an inner wall known as the septum. A VSD can occur in the wall between the ventricles (or lower chambers of the heart). For many children born with VSD, the opening eventually closes in the first few years of life. Its ability to close depends on VSD location within the wall and the size of the VSD.

Symptoms of a Ventricular Septal Defect

Symptoms may or may not be obvious. A heart murmur may be the only sign. While your child’s doctor may hear the murmur at birth, it may not be possible to hear until your baby is 6 to 8 weeks old. Babies with larger VSDs are more likely to show symptoms at birth than those with atrial septal defects (ASDs). Those who have medium or large VSDs can develop pulmonary overcirculation (too much blood flow to the lung arteries) and congestive heart disease. 

If the VSD is large enough and there is pulmonary overcirculation, symptoms usually appear in the first two months of life and may include: 

• Heart murmur (abnormal heart sound)
• Trouble eating or gaining weight (failure to thrive)
• Fast breathing or working hard to breathe
• Tiring easily
• Excessive sweating

Depending on size and location of the opening, symptoms indicating a VSD may not be noticeable until months to years later. A VSD may not apparent until adulthood in rare cases.

Diagnosis of a Ventricular Septal Defect

A heart murmur, which is associated with a ventricular septal defect, is detected by listening to the chest through a stethoscope. Your child’s doctor may hear abnormal heart sounds or a murmur that indicates blood is not flowing smoothly through the heart. Additional exams and tests may be performed to see the size of the opening, determine whether there is more than one abnormal hole and learn how the VSD affects the heart and lungs. These tests include:

• Electrocardiogram (EKG/ECG). This is a simple, painless test designed to record the heart’s electrical activity through electrodes attached to the skin. It can also be used to diagnose heart conditions and monitor any problems.
• Chest X-ray. X-rays provide yet a different set of images, showing whether the heart is enlarged or the lungs have extra fluid, which is a sign of heart failure.
• Pulse Oximetry. This simple test gives an estimate of how much oxygen is in the blood. A small sensor is attached to a finger or toe to measure oxygen levels.
• Echocardiography (or Echo). A painless ultrasound uses sound waves to create pictures of the heart. Doctors can see if there are any problems with the heart formation or the way it works. Once diagnosed, your child may have further echo images to monitor changes.
• Cardiac Catheterization. This procedure is rarely needed in the case of a VSD, but may be necessary in more complex disease. Done under local anesthesia, cardiac catheterization can be used for diagnosis and/or repair, depending on your child’s VSD. A small, flexible tube is threaded through a vein in the arm, upper thigh or neck. When it is used as a diagnostic step, special dye is injected to allow the doctor to see how the blood flows through the heart and blood vessels. Pressure inside the heart can also be measured to determine if an opening is causing blood to mix from both sides of the heart.